An Action Potential from a Motor Neuron Arriving at the Neuromuscular

Multiple Choice

An action potential from a motor neuron arriving at the neuromuscular junction (NMJ) triggers a series of events leading to muscle contraction. Of the following four events, which occurs after the others?

A) acetylcholine (ACh) release
B) the myosin-binding sites on actin are exposed
C) depolarization of the muscle cell
D) release of Ca2+ from the sarcoplasmic reticulum